The hepatic galactosyl receptor system: Two different ligand dissociation pathways are mediated by distinct receptor populations

Paul H. Weigel, Benjamin L. Clarke, Janet A. Oka

Research output: Contribution to journalArticlepeer-review

18 Scopus citations

Abstract

After internalization of 125I-asialo-orosomucoid (ASOR) by isolated rat hepatocytes, ligand dissociates by two kinetically distinct pathways (Oka and Weigel, J. Biol. Chem. 257, 10,253, 1983). These slow and fast dissociation pathways correspond to two functionally different subpopulations of cell surface galactosyl receptors designated, respectively, State 1 and State 2 receptors. Freshly isolated cells or cells equilibrated below 24°C express only State 1 receptors. Cells equilibrated at 37°C express both State 1 and State 2 receptors. Ligand dissociation after internalization of surface-bound 125I-ASOR was measured using the permeabilizing detergent, digitonin. The slow dissociation pathway was mediated by State 1 receptors and was the only pathway expressed by cells which were freshly isolated or had been equilibrated at 24°C. State 2 receptors are expressed at temperatures above about 20°C, and both the fast and slow dissociation pathways occurred in cells equilibrated at 37°C. State 2 receptors therefore mediate the rapid dissociation pathway. Dissociation and subsequent degradation of specifically bound ligand routed in either pathway were complete, respectively, within 3 and 6 hrs.

Original languageEnglish (US)
Pages (from-to)43-50
Number of pages8
JournalBiochemical and Biophysical Research Communications
Volume140
Issue number1
DOIs
StatePublished - Oct 15 1986

Fingerprint

Dive into the research topics of 'The hepatic galactosyl receptor system: Two different ligand dissociation pathways are mediated by distinct receptor populations'. Together they form a unique fingerprint.

Cite this